There has been conventionally known a power supply device carrying an inverter for driving a compressor motor used in a refrigeration-cycle applied device. For example, in a conventional technique described in Patent Literature 1 listed below, a switching element is operated once or more in synchronization with a half period of a power supply device, so that a conduction angle of an input current is made larger to improve a power factor and reduce harmonic components of the input current (for example, Patent Literature 1 listed below).